US10680333B2 - Loop antenna - Google Patents

Loop antenna Download PDF

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Publication number
US10680333B2
US10680333B2 US15/542,338 US201615542338A US10680333B2 US 10680333 B2 US10680333 B2 US 10680333B2 US 201615542338 A US201615542338 A US 201615542338A US 10680333 B2 US10680333 B2 US 10680333B2
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loop
amplification
main
main loop
resistance
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US20180277953A1 (en
Inventor
Ai-Ichiro Sasaki
Tsutomu Mizota
Hiroki Morimura
Osamu Kagami
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Nippon Telegraph and Telephone Corp
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Nippon Telegraph and Telephone Corp
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Assigned to NIPPON TELEGRAPH AND TELEPHONE CORPORATION reassignment NIPPON TELEGRAPH AND TELEPHONE CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: KAGAMI, OSAMU, MIZOTA, Tsutomu, MORIMURA, HIROKI, SASAKI, AI-ICHIRO
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q7/00—Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00—Details of, or arrangements associated with, antennas
    • H01Q1/36—Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith
    • H01Q1/38—Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith formed by a conductive layer on an insulating support

Definitions

  • the present invention relates to a loop antenna which can contribute to an increase of an area of a radio system using a magnetic field.
  • a radio system utilizing a magnetic field has been conventionally proposed. Unlike radio waves, the magnetic field hardly interacts with human bodies and dielectric materials, and is thus advantageous in forming a definite radio area which is undisrupted by human bodies and obstacles. Moreover, the distance attenuation characteristic of a radio wave is 20 dB/dec., while the distance attenuation characteristic of a magnetic field is 60 dB/dec. Thus, the magnetic field is suitable in the case of definitely defining a radio area boundary.
  • the distance attenuation characteristic (60 dB/dec.) of the magnetic field which is steeper than that of the radio wave is a disadvantageous factor in the case of increasing the radio area.
  • a current supplied from a transmitter has to be increased.
  • the present invention has been made in view of the problems described above and an objective thereof is to provide a loop antenna which can contribute to an increase of an area of a radio system using a magnetic field.
  • a loop antenna in a first aspect of the present invention includes a main loop which is an open loop connected to a signal source or a reception circuit; and an amplification loop which is a closed loop having a same shape as the main loop, and the main loop and the amplification loop are arranged on a same surface of a flat substrate formed of an insulator.
  • a loop antenna in a second aspect of the present invention includes: a main loop which is an open loop connected to a signal source or a reception circuit; and an amplification loop which is a closed loop having a same shape as the main loop, and the main loop and the amplification loop are arranged on different surfaces of a flat substrate formed of an insulator or on different flat substrates in a structure in which a plurality of flat substrates are stacked one on top of another.
  • a current sufficiently larger than a current flowing through the main loop can be accumulated in the amplification loop. As a result, a large magnetic field can be generated.
  • an effect in which a large current is accumulated in the amplification loop in the reception of the magnetic field allows the main loop to receive a reception current larger than that in the case where no amplification loop is used.
  • the loop antenna of the present invention can contribute to an increase of an area of a radio system using a magnetic field.
  • FIG. 1 is a diagram illustrating an example of a loop antenna in a first embodiment.
  • FIG. 2 is a diagram illustrating an example of a loop antenna in a second embodiment.
  • FIG. 3 is a diagram illustrating an example of a loop antenna in a third embodiment.
  • FIG. 4 is a diagram illustrating an example of a loop antenna in a fourth embodiment.
  • FIG. 5 is a diagram illustrating a relationship among a current I 2 of an amplification loop 2 and capacitances C 1 and C 2 .
  • FIG. 1 is a diagram illustrating an example of a loop antenna in a first embodiment.
  • the loop antenna is a resonant loop antenna and includes a main loop 1 and an amplification loop 2 .
  • the main loop 1 is formed on a flat substrate (not illustrated) formed of an insulator, includes terminals T, T for connection to a signal source 5 or a reception circuit (not illustrated), and is an open loop.
  • the number of turns is one.
  • FIG. 1 is a diagram of an example in which the signal source 5 is connected to the main loop 1 .
  • a resistance R 1 and a capacitance C 1 are connected to the main loop 1 in series.
  • the amplification loop 2 is formed very close to the main loop 1 , on the same surface of the flat substrate on which the main loop 1 is formed.
  • the amplification loop 2 includes no terminals and is a closed loop. The number of turns is one.
  • the amplification loop 2 is arranged inside the main loop 1 .
  • the distance d between the main loop 1 and the amplification loop 2 is, for example, equal to or smaller than one-tenth of a square root of the area of a region surrounded by the main loop 1 or the amplification loop 2 .
  • a resistance R 2 and a capacitance C 2 are connected to the amplification loop 2 in series.
  • I 2 depends on multiple factors such as a frequency, R 1 , R 2 , C 1 , C 2 , an internal resistance R 0 of the signal source 5 , and the shape of the loop. Accordingly, it is desirable to maximize I 2 by adjusting R 1 , R 2 , C 1 , and C 2 .
  • FIG. 1 illustrates an example in which the loop antenna is connected to the signal source 5 and is used as a transmission antenna
  • the loop antenna may be connected to a reception circuit instead of the signal source 5 and be used as a reception antenna.
  • a magnetic field received from the outside causes a large AC current I 2 to be accumulated in the amplification loop 2 .
  • the AC current I 1 flowing through the main loop 1 is larger than that in the case where there is no amplification loop 2 .
  • I 1 can be maximized by setting R 1 , R 2 , C 1 , and C 2 depending on the frequency, the shape of the loop, and the like. The area of the magnetic field can be thereby increased also for the other party.
  • the loop antenna in the first embodiment can increase the area of the radio system utilizing the magnetic field.
  • the amplification loop 2 may be arranged outside the main loop 1 .
  • the loops are arranged such that one loop includes the other loop therein.
  • the amplification loop 2 has the same shape (geometric shape) as the main loop.
  • the same shape includes a similar shape. The same applies to the embodiments to be described later.
  • R 1 , R 2 , C 1 , and C 2 may not be used. The same applies to the embodiments to be described later.
  • FIG. 2 is a diagram illustrating an example of a loop antenna in a second embodiment.
  • the number of turns is one in both of the main loop 1 and the amplification loop 2 .
  • the number of turns is three in both loops.
  • Other configurations are the same as those in the first embodiment.
  • the amplification loop 2 is arranged inside the main loop 1 .
  • the number of turns in the present invention is arbitrary and any number of turns is effective.
  • the number of turns may vary between the main loop 1 and the amplification loop 2 .
  • equalizing the number of turns in the main loop 1 and the number of turns in the amplification loop 2 can increase the mutual inductance and thus increase the effect of amplifying the current. Accordingly, it is preferable to equalize the number of turns in the main loop 1 and the number of turns in the amplification loop 2 .
  • FIG. 3 is a diagram illustrating an example of a loop antenna in a third embodiment.
  • the main loop 1 and the amplification loop 2 are provided on the same flat surface of the flat substrate and the amplification loop 2 is arranged inside or outside the main loop 1 to be provided close thereto.
  • the main loop 1 is formed on a front surface of the flat substrate and the amplification loop 2 is formed on a back surface of the same flat substrate.
  • Other configurations are the same as those in the first embodiment.
  • the main loop 1 and the amplification loop 2 only needs to be formed separately on the different surfaces (front and back surfaces) of the flat substrate. Accordingly, the configuration may be such that the main loop 1 is formed on the back surface of the flat substrate and the amplification loop 2 is formed on the front surface of the same flat substrate.
  • Forming the main loop 1 and the amplification loop 2 respectively on the front and back surfaces of the same flat substrate allows the main loop 1 and the amplification loop 2 to have the same shape and also to be provided close to each other.
  • the main loop 1 and the amplification loop 2 can have the same shape and the same size, that is exactly the same shape.
  • the distance between the main loop 1 and the amplification loop 2 is substantially equal to the thickness of the flat substrate. The distance is equal to or smaller than one-tenth of a square root of the area of a region surrounded by the main loop 1 or the amplification loop 2 .
  • the main loop 1 and the amplification loop 2 have the same shape, it is possible to achieve the magnetic coupling coefficient close to 1 between the main loop 1 and the amplification loop 2 and increase the mutual inductance. Accordingly, larger I 2 can be obtained relative to constant I 1 when the signal source 5 is used, and larger I 1 can be obtained relative to constant I 2 when the reception circuit is used. In other words, the area of the magnetic field can be increased.
  • the main loop 1 and the amplification loop 2 may be arranged respectively on different flat substrates.
  • the distance between the main loop 1 and the amplification loop 2 is substantially equal to any integral multiple (single, double, . . . ) of the thickness of each flat substrate. The distance is equal to or smaller than one-tenth of a square root of the area of a region surrounded by the main loop 1 or the amplification loop 2 .
  • FIG. 4 is a diagram illustrating an example of a loop antenna in a fourth embodiment.
  • the fourth embodiment has a configuration in which the number of turns is three in the loop antenna of the third embodiment. Other configurations are the same as those in the third embodiment.
  • forming the main loop 1 and the amplification loop 2 with many turns on the same surface of the flat substrate has a problem that the difference between the area of the region surrounded by the main loop 1 and the area of the region surrounded by the amplification loop 2 is large. When this difference is too large, the mutual inductance between the main loop 1 and the amplification loop 2 decreases and it is difficult to increase the area of the magnetic field (amplify I 2 ).
  • the main loop 1 and the amplification loop 2 are arranged, for example, on the different surfaces of the same flat substrate. Accordingly, the main loop 1 and the amplification loop 2 can be provided close to each other even when the number of turns in each of the main loop 1 and the amplification loop 2 is large. The same applies to the case where the main loop 1 and the amplification loop 2 are arranged on different flat substrates in the structure in which flat substrates are stacked one on top of another.
  • the mutual inductance between the main loop 1 and the amplification loop 2 does not decrease and the area of the magnetic field can be increased. This effect can be increased by increasing the number of turns.
  • Equalizing the number of turns in the main loop 1 and the number of turns in the amplification loop 2 can further increase the mutual inductance and increase the area of the magnetic field.
  • the loop antenna in a fifth embodiment is one in which the capacitances connected to the main loop 1 and the amplification loop 2 are optimized.
  • Other configurations are the same as those in the first to fourth embodiments.
  • the frequency f of a signal generated by the signal source 5 is 10 MHz
  • the resistance R 1 connected to the main loop 1 is 25 ⁇
  • the resistance R 2 connected to the amplification loop 2 is 1 ⁇
  • the internal resistance R 0 of the signal source 5 is 25 ⁇ .
  • the resistance R 2 is smaller than the sum of the resistance R 1 and the internal resistance R 0 .
  • the main loop 1 and the amplification loop 2 both have the same self-inductance L of 1 pH.
  • the self-inductance of a loop depends on the geometric shape thereof, the self-inductance of the main loop 1 and the self-inductance of the amplification loop 2 can be easily equalized by forming the main loop 1 and the amplification loop 2 in the same geometric shape.
  • FIG. 5 is a diagram illustrating a relationship among the current I 2 of the amplification loop 2 and the capacitances C 1 and C 2 .
  • I 2 is simulated under the aforementioned conditions with the capacitances C 1 and C 2 being variables, the result of FIG. 5 is obtained. I 2 is largest when C 1 is close to 30 pF and C 2 is close to 220 pF.
  • the current amplification effect is greatest at 10 MHz.
  • I 1 power consumption of the signal source 5
  • I 2 is 70 mA or larger
  • a current which is equal to or larger than the seven times the current I 1 can flow as I 2 .
  • the amplitude of the magnetic field which can be generated can be thus amplified to be seven times or more.
  • the current flowing through the loop antenna can be amplified without increasing the current supplied from the signal source 5 , a large magnetic field can be generated with low power consumption. As a result, the area of the radio system utilizing the magnetic field can be increased.

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US15/542,338 2015-03-18 2016-03-07 Loop antenna Active 2036-03-29 US10680333B2 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2015-054362 2015-03-18
JP2015054362A JP6077036B2 (ja) 2015-03-18 2015-03-18 ループアンテナ
PCT/JP2016/057011 WO2016147934A1 (fr) 2015-03-18 2016-03-07 Antenne cadre

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US20180277953A1 US20180277953A1 (en) 2018-09-27
US10680333B2 true US10680333B2 (en) 2020-06-09

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US (1) US10680333B2 (fr)
EP (1) EP3273539B1 (fr)
JP (1) JP6077036B2 (fr)
CN (1) CN107431276B (fr)
WO (1) WO2016147934A1 (fr)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6263662B1 (ja) 2017-06-19 2018-01-17 日本電信電話株式会社 アンテナ回路
JP6243569B1 (ja) * 2017-06-20 2017-12-06 日本電信電話株式会社 ループアンテナ

Citations (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4395714A (en) * 1980-03-03 1983-07-26 Pioneer Electronic Corporation Antenna array system usable for AM/FM receiver
US6020856A (en) 1995-05-30 2000-02-01 Sensormatic Electronics Corporation EAS system antenna configuration for providing improved interrogation field distribution
JP2001185939A (ja) 1999-12-24 2001-07-06 Mitsubishi Electric Corp アンテナコイル及び電磁誘導型非接触データキャリアシステム
US20020113739A1 (en) * 2000-12-14 2002-08-22 Howard David Amundson Arrayed-segment loop antenna
US6567050B1 (en) * 2001-12-17 2003-05-20 Briggs James B Loop antenna compensator
US20050057422A1 (en) * 2003-09-01 2005-03-17 Matsushita Electric Industrial Co., Ltd. Gate antenna device
US20050092845A1 (en) * 2003-11-03 2005-05-05 Forster Ian J. Self-compensating antennas for substrates having differing dielectric constant values
JP2005275871A (ja) 2004-03-25 2005-10-06 Matsushita Electric Ind Co Ltd 挿入型記憶媒体装置および無線通信媒体付記憶装置
US20100187913A1 (en) * 2008-08-20 2010-07-29 Smith Joshua R Wireless power transfer apparatus and method thereof
US20100253587A1 (en) * 2009-03-03 2010-10-07 Delphi Delco Electronics Europe Gmbh Antenna for reception of satellite radio signals emitted circularly, in a direction of rotation of the polarization
JP2011045045A (ja) 2009-07-23 2011-03-03 Nippon Soken Inc 送受電用アンテナ及び送電器
JP2011086009A (ja) 2009-10-13 2011-04-28 Tdk Corp Ｒｆｉｄ及び無線通信機
US20110115607A1 (en) * 2009-11-19 2011-05-19 Panasonic Corporation Transmitting / receiving antenna and transmitter / receiver device using the same
US20110281535A1 (en) * 2010-05-14 2011-11-17 Qualcomm Incorporated Controlling field distribution of a wireless power transmitter
US20120094599A1 (en) * 2009-06-30 2012-04-19 Panasonic Corporation Antenna device and portable wireless apparatus provided with same
US20120208474A1 (en) * 2011-02-15 2012-08-16 Panasonic Corporation Transmission/reception antenna and transmission/reception device using same
JP2013125991A (ja) 2011-12-13 2013-06-24 Nippon Telegr & Teleph Corp <Ntt> 無線通信システム
US20130194540A1 (en) * 2012-01-26 2013-08-01 Randall Braxton Pugh Ophthalmic lens assembly having an integrated antenna structure
US20130328409A1 (en) * 2012-06-12 2013-12-12 Georgia Tech Research Corporation Misalignment Insensitive Wireless Power Transfer
JP2014135539A (ja) 2013-01-08 2014-07-24 Nippon Telegr & Teleph Corp <Ntt> 無線通信システム
JP2014135538A (ja) 2013-01-08 2014-07-24 Nippon Telegr & Teleph Corp <Ntt> 携帯端末装置および無線通信システム
US20140266966A1 (en) * 2013-03-15 2014-09-18 Verifone, Inc. Multi-loop antenna system for contactless applications
WO2015008704A1 (fr) 2013-07-16 2015-01-22 株式会社村田製作所 Dispositif d'antenne et dispositif de communication
US20170207535A1 (en) * 2014-07-30 2017-07-20 Renesas Electronics Corporation Loop antenna and communication control device

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011066759A (ja) * 2009-09-18 2011-03-31 Sony Chemical & Information Device Corp アンテナ装置、及び、通信装置

Patent Citations (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4395714A (en) * 1980-03-03 1983-07-26 Pioneer Electronic Corporation Antenna array system usable for AM/FM receiver
US6020856A (en) 1995-05-30 2000-02-01 Sensormatic Electronics Corporation EAS system antenna configuration for providing improved interrogation field distribution
JP2001185939A (ja) 1999-12-24 2001-07-06 Mitsubishi Electric Corp アンテナコイル及び電磁誘導型非接触データキャリアシステム
US20020113739A1 (en) * 2000-12-14 2002-08-22 Howard David Amundson Arrayed-segment loop antenna
US6567050B1 (en) * 2001-12-17 2003-05-20 Briggs James B Loop antenna compensator
JP2005102101A (ja) 2003-09-01 2005-04-14 Matsushita Electric Ind Co Ltd ゲートアンテナ装置
US20050057422A1 (en) * 2003-09-01 2005-03-17 Matsushita Electric Industrial Co., Ltd. Gate antenna device
US20050092845A1 (en) * 2003-11-03 2005-05-05 Forster Ian J. Self-compensating antennas for substrates having differing dielectric constant values
JP2005275871A (ja) 2004-03-25 2005-10-06 Matsushita Electric Ind Co Ltd 挿入型記憶媒体装置および無線通信媒体付記憶装置
US20100187913A1 (en) * 2008-08-20 2010-07-29 Smith Joshua R Wireless power transfer apparatus and method thereof
US20130057080A1 (en) 2008-08-20 2013-03-07 Joshua R. Smith Wireless power transfer apparatus and method thereof
US20100253587A1 (en) * 2009-03-03 2010-10-07 Delphi Delco Electronics Europe Gmbh Antenna for reception of satellite radio signals emitted circularly, in a direction of rotation of the polarization
US20120094599A1 (en) * 2009-06-30 2012-04-19 Panasonic Corporation Antenna device and portable wireless apparatus provided with same
JP2011045045A (ja) 2009-07-23 2011-03-03 Nippon Soken Inc 送受電用アンテナ及び送電器
JP2011086009A (ja) 2009-10-13 2011-04-28 Tdk Corp Ｒｆｉｄ及び無線通信機
US20110115607A1 (en) * 2009-11-19 2011-05-19 Panasonic Corporation Transmitting / receiving antenna and transmitter / receiver device using the same
US20110281535A1 (en) * 2010-05-14 2011-11-17 Qualcomm Incorporated Controlling field distribution of a wireless power transmitter
JP2013534074A (ja) 2010-05-14 2013-08-29 クアルコム，インコーポレイテッド 無線電力伝送器の電磁界分布の制御
US20120208474A1 (en) * 2011-02-15 2012-08-16 Panasonic Corporation Transmission/reception antenna and transmission/reception device using same
JP2013125991A (ja) 2011-12-13 2013-06-24 Nippon Telegr & Teleph Corp <Ntt> 無線通信システム
US20130194540A1 (en) * 2012-01-26 2013-08-01 Randall Braxton Pugh Ophthalmic lens assembly having an integrated antenna structure
US20130328409A1 (en) * 2012-06-12 2013-12-12 Georgia Tech Research Corporation Misalignment Insensitive Wireless Power Transfer
JP2014135539A (ja) 2013-01-08 2014-07-24 Nippon Telegr & Teleph Corp <Ntt> 無線通信システム
JP2014135538A (ja) 2013-01-08 2014-07-24 Nippon Telegr & Teleph Corp <Ntt> 携帯端末装置および無線通信システム
US20140266966A1 (en) * 2013-03-15 2014-09-18 Verifone, Inc. Multi-loop antenna system for contactless applications
WO2015008704A1 (fr) 2013-07-16 2015-01-22 株式会社村田製作所 Dispositif d'antenne et dispositif de communication
US20170207535A1 (en) * 2014-07-30 2017-07-20 Renesas Electronics Corporation Loop antenna and communication control device

Non-Patent Citations (10)

* Cited by examiner, † Cited by third party
Title
International Preliminary Report on Patentability, PCT Patent Application No. PCT/JP2016/057011 dated Sep. 28, 2017.
International Search Report, PCT Patent Application No. PCT/JP2016/057011, dated May 10, 2016.
Lee et al., "Enhanced Loop Structure of NFC Antenna for Mobile Handset Applications, Hindawi Publishing Corporation International Journal of Antennas and Propagation vol. 2014, Article ID 187029" (Year: 2014). *
Li et al., "Investigation of Circularly Polarized Loop Antennas With a Parasitic Element for Bandwidth Enhancement, IEEE Transactions on Antennas and Propagation, vol. 53, No. 12, Dec. 2005" (Year: 2005). *
Office Action, Chinese Patent Application No. 201680015874.1, dated Apr. 28, 2019, 17 pages.
Office Action, European Patent Application No. 16764764.3, dated May 8, 2019, 6 pages.
Office Action, European Patent Application No. 16764764.3, dated Oct. 17, 2019, 6 pages.
Office Action, Japanese Patent Application No. 2015-054362, dated May 10, 2016.
Office Action, Japanese Patent Application No. 2015-054362, dated Sep. 13, 2016.
Supplementary European Search Report, European Patent Application No. 16764764.3, dated Aug. 28, 2018.

Also Published As

Publication number Publication date
EP3273539A1 (fr) 2018-01-24
CN107431276B (zh) 2020-02-28
WO2016147934A1 (fr) 2016-09-22
US20180277953A1 (en) 2018-09-27
JP6077036B2 (ja) 2017-02-08
CN107431276A (zh) 2017-12-01
EP3273539B1 (fr) 2020-10-14
JP2016174327A (ja) 2016-09-29
EP3273539A4 (fr) 2018-09-26

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